Preposition
After lunch, I felt sleepy.
Subordinating Conunction
After I worked twelve hours, I felt tired.

As

Preposition
As the chief , I am responsible for the conduct of my cadets.
Subordinating Conjucntion.
As I worked my way up the levels , I was more confident in finishing the game.

Before

Before Ram came Sita

Always strecth before you begin to work out.

under, over, near, beside

Place

Place your book under the table.

(to, toward, into, through, etc.)

Direction (to, toward, into, through, etc.)
What is the way to the temple?

at

Time at, etc.)

I will meet you at 5 o clock

By

Mesaure

We buy our olive oil by the 16 kilo container

like

Similarity
She looks like her mother.

as

Capacity
He worked as fireman.

Such as

Examples

of

Mesaure, Partition,Possesion.

They painted the front of the building white and green.

He broke the top of the table with his fist.

1 pound of flesh

for

Purpose

“He went to the store for milk and bread.
TIP:
Never, Never use for + verb + ing to express the purpose of the verb.
Example: “He went to the store for buying milk and bread.” This is wrong usage and a common mistake!